Nor'easters

Nor'easters are storms that move north up the East Coast of the United States. Although
they can occur at any time of the year, severe winter nor'easters are especially
dangerous. Cold temperatures and high winds combine to produce unhealthy
wind chills. Strong northeasterly winds that blow in off the ocean cause
huge waves that crash onto Atlantic beaches. This often causes beach erosion
and property damage. Heavy precipitation can accumulate very quickly in
the form of rain, freezing rain, sleet, or snow.

A successful winter storm forecast should say what kind of precipitation
(rain, freezing rain, or snow) will fall, when it will start, how long
it will last, how hard it will be, and exactly where it will fall. This
is especially hard for meteorologists when dealing with nor'easters, which
are often unpredictable. So, what clues does a meteorologist look for
when predicting a nor'easter?

Nor'easters
usually develop off the coast of North Carolina when the cold Labrador
current and the warm Gulf Stream current meet. The contrast in the air
temperatures above these currents help form a low pressure system. At
the same time over Canada, winds circulate in a clockwise motion around
a high pressure system. These winds dip deeply into the Northeastern United
States bringing cold Canadian temperatures to support the formation of
snow.

The
low begins to move north up the coast. At the same time, air rushes counterclockwise
around it, bringing winds that blow from the Northeast toward the Southwest.
These winds pick up moisture from the ocean. The movement of the winds
and precipitation from the Northeast is why this storm is called a nor'easter.
Picture a giant, wet Frisbee spinning counterclockwise as it flies north
along the Atlantic Coast and you'll see the movement of a nor'easter.

Lift
causes the moisture to rise and form clouds and precipitation. If the
clouds are trapped east of the Appalachian Mountains, they drop precipitation
on areas along the coast. A slow-moving storm system picks up more moisture
and produces more precipitation than a fast-moving system.

So, are you ready to try your hand at meteorology? Go back to
your team area in the student section and learn more about how
to do your job. Good Luck.